Drilling and automatic centering device.



1%. 757,950. PATENTED APR. 19, 1904. .J. J. McBLWAIN & E. A. YOUNG.DRILLING AND AUTOMATIC GBNTERING DEVICE.

APPLICATION FILED NOV. 18, 1903.

'Zdmaaec? fnvenaora ya 6? fir nesJ/ll f/wa/h I UNITED STATES PatentedApril 19, 1904.

PATENT OFFICE.

JAMES J MoELlVAIN AND ELMER A. YOUNG, OF ALLEGHENY,

PENNSYLVANIA.

DRlLLlNG AND AUTOMATIC CENTERING DEVICE.

SPECIFICATION forming part of Letters Patent No. 757,950, dated April19, 1904.

Application filed November 18, 1903. Serial No. 181,631- (No model.)

To all whom it may concern:

Be it known that we, J AMES J MoELWAIN and Emma A. YOUNG, citizens ofthe United States of America, residing at Allegheny, in the county ofAllegheny and State of Pennsylvania, have invented certain new anduseful Improvements in Drilling and Automatic Centering Devices, ofwhich the following is a specification, reference being had therein tothe accompanying drawings.

This invention relates to certain new and useful improvements in adrilling and automatic centering tool, and relates more particularly toa tool which is adapted to automatically center and drill the end of thepiece of work, the same being designed to beused in a drill-press,lathe, or other similar machines.

The object of this invention is to provide a tool whereby the piece ofwork may be automatically centered and then drilled at its cen-.

tral point.

A further object of this invention is to so construct a tool that thecenter of an irregular-shaped piece of work- 5. -e., the point mostcommonly central to its diflerent radial peripheral irregularitios maybe suitably drilled, whereby the same may be held in the lathe or othertool in which the piece of work is to be machined.

A still further object of this invention is to so construct a tool thatthe friction of operation of the same will be minimized and that anefficient and simple device may be prodnced.

\Vith the above and other objects in view the invention consists in thenovel construction, combination, and arrangement of parts, to behereinafter more fully described, and specilically pointed out in theclaims.

in describing the invention in detail reference is had to theaccompanying drawings, forming a part of this application, and whereinlike numerals of reference indicate like parts throughout the severalviews, in which Figure 1 is an elevation, partly in section, of ourimproved device. Fig. 2 is a fragmentary View of a drill-press, showingOlll improved tool applied thereto. Fig. 3 is a sectional view taken online 3 3 of Fig. 1.

Referring to the drawings, the referencenumeral 1 indicates a portion ofthe drillspindle which is adapted to be fitted into the spindle 2 of thedrill-press or lathe, and 3 indicates an extension of the portion 1, inthe outer end of which the drill 4 is mounted. The portion 5 of thedrill-spindle has provided on its face a ball-race 6 and a sleeve 7which is slidably mounted on the portion 3 of the spindle and isprovided in its face with a ball-race 8, and balls 9 are mounted betweenthe part 5 and sleeve 7, as clearly indicated in Fig. 1.

Secured in the end of the spindle 3 by the screw-threaded connection 10is a drill 4, which is preferably formed out of hexagon stock, wherebythe same may be secured in place by a socket-wrench, and formed in theportion 3 of the spindle is a way 11, in which a feather or key 12,secured within the sleeve 14 by screws 15, is adapted to slide. The endsof this sleeve 14 are provided with ball-races 16 and 16, and while thesaid sleeve has a nice fit over spindle 3 it is somewhat loosely mountedwithin the portion 17 of the centering-bell 1.8. The ball-race 19 isformed in the cone' 18, as shown in Fig. 1, and the cap 20 is adapted tobe connected to the portion 17 of the centering-bell by thescrew-threaded connection 21 thereof and has a ball-race 22 provided onits under side, and a series of balls 23 are placed between theball-race 16 and the sleeve 14, and balls 24 are placed between theball-race 16 in the sleeve and the ball-race of the cap 26. A spring 25is mounted between the sleeve 7 and the cap 20, whereby the saidcenteringbell is normally held in its lowered position. A sight 26 isprovided, which consists in cutting away a portion of the bell, wherebythe operation of the drill 4: upon the piece of work which has beencentered-in the said bell may be observed by the operator.

In assembling our device the sleeve 7 is placed in position on thespindle 3 and the balls 9 placed between the race in the sleeve and therace in the portion 5 of the spindle, and a spring 25 is then placed inposition on the spindle and the cap 20 placed on said spindle. The key12 is then placed in position in the slot 11 of the spindle and thesleeve 14 slid over the said key and spindle to such a position that thescrews 15 may be placed in position whereby to connect the said key withthe sleeve. The spring is then compressed by forcing the sleeve on theouter ends of the spindle upwardly and the balls 19 placed in positionwithin the centering-bell, which is then placed in position over thesleeve. The balls 24 are then placed in position between the cap and thesleeve, and the said cap is then screwed into the upper portion of thecentering-bell. The bell is then forced rearwardly and the drill 4:placed in position in the end of the spindle by a suitablesocket-wrench. The device is then in condition for operation, which willbe as follows: The portion 1 of the spindle having been suitably securedin the spindle 2 of the drill-press, lathe, or similar machine, thepiece of work which is to be centered and drilled. has its one endplaced in the centering-bell 27 or otherwise held, and the spindle 2 isthen operated, whereby to bring the centering-bell 18 against the otherend of the work, thereby accurately centering the same, and furthermovement of the spindle 2, which would now be rotating, would causespindle to move through sleeve 14 in centering-bell, whereby the spring25 will be compressed and the drill 4 thus brought into operativerelation to the piece of work, whereby the center of the same will besuitably drilled. This movement of the spindle 3 through thecentering-bell is permitted by the sleeve 1 being permitted by keyway orfeather 12 to slide in the slot 11, formed in the spindle 3, the saidsleeve 14 of course turning with said spindle, due to this featherconnection, and the friction of the under thrust of the same beingminimized by the ball-bearings, which are provided, as herein described.

While we have herein shown and described the invention in detail, itwill be observed that various slight changes may be made in the detailsof construction without departing from the general spirit of ourinvention.

Having fully described our invention, what we claim as new, and d esireto secure by Letters Patent, is

1. The combination of a rotary spindle having a tool-socket and enlargedportion or shoulder, a sleeve bearing against said shoulder, a bell,arranged on said spindle and formed with a central cavity, a capscrewing into said cav ity, a spring bearing against said cap and sleeveand a second sleeve arranged in the cavity in the bell and slidablykeyed to said spindle, substantially as described.

2. In adevice of the character described, the combination of acentering-bell, a sleeve rotatably mounted in said bell, ball bearingsformed between each end of said sleeve and bell, a drill-spindle uponwhich said sleeve and hell are mounted, a sleeve mounted on the upperportion of said spindle, ball-bearings mounted between said sleeve andupper portion of the spindle, and a spring mounted between saidlast-mentioned sleeve and said bell, substantially as described.

3. In a device of the character describechthe combination of acentering-bell, a sleeve rotatably mounted in said-bell, a spindleslidably mounted Within said sleeve by a feather connection,ball-bearings formed between each end of said sleeve and said bell, asleeve mounted on the said drill-spindle intermediate its length, aball-bearing formed between the upper portion of said spindle and saidsleeve, a

spring mounted between said last-mentioned.

In testimony whereof we affix our signatures in the presence of twowitnesses.

JAMES J. MOEL'WAIN. ELMER A. YOUNG.

Witnesses:

A. M. WILSON, E. E. POTTER.

